Sylvia Did Not Killer Dr. Cortes
Warning This Section Does Contain Spoilers
There was the possibility that Sylvia killed Dr. Cortes when she came to the facility to visit, or at the very least, to find out information on Jasper. But the last paragraph in the letter from this episode (episode five) tells us that she is going away because she can't believe that she ALMOST put people in danger by helping him. This tells us that she didn't hurt anyone, let alone kill anyone. So she is innocent of any violent crime. Only guilty of planning things that haven't come to fruition.